Cornus plant named ‘SUMMER GOLD’

ABSTRACT

A new cultivar of  Cornus  plant named ‘SUMMER GOLD’ whose leaves are variegated mid-green with a prominent wide gold margin and whose variegation persists throughout the summer. In combination these traits set ‘SUMMER GOLD’ apart from all other existing varieties of  Cornus  known to the inventor.

Genus: CORNUS.

Species: kousa.

Denomination: ‘SUMMER GOLD’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Cornuskousa, or kousa dogwood that is grown for use as a landscape tree. It isknown botanically as Cornus kousa and will be referred to hereinafter bythe cultivar name ‘SUMMER GOLD’.

‘SUMMER GOLD’ arose and was selected by the inventor at the inventor'snursery in Molalla, Oreg., as a chance seedling in a field-grown crop ofCornus kousa (species, unpatented) in 2002.

The new Cornus variety ‘SUMMER GOLD’ is an upright tree characterized byvariegated foliage. The leaves of ‘SUMMER GOLD’ are predominantly midgreen in color and exhibit a prominent gold margin. The foliagevariegation is maintained through the summer.

‘SUMMER GOLD’ may be compared with the species parent as follows:Whereas the species parent bears non-variegated green leaves, ‘SUMMERGOLD’ exhibits variegated foliage as described herein.

The closest known comparison varieties known to the breeder are the twovariegated cultivars Cornus kousa ‘Okhan’ (unpatented) and theinventor's variety Cornus kousa ssp. chinensis ‘Tri-Splendor’ (U.S.Plant Pat. No. 20,008).

When compared with ‘Okhan’, ‘SUMMER GOLD’ bears wider and flatter leavesand is more vigorous in its growth and branching.

When compared with ‘Tri-Splendor’, ‘SUMMER GOLD’ produces more lateralbranches and retains its variegation throughout the summer, whereas‘Tri-Splendor’ becomes increasingly non-variegated as summer progresses.

‘SUMMER GOLD’ was first asexually propagated by the inventor in Molalla,Oreg. in 2005. Asexual propagation was accomplished by grafting ‘SUMMERGOLD’ onto seedling understock. Since that time, under carefulobservation, the distinguishing characteristics of ‘SUMMER GOLD’ havebeen determined stable and uniform, and are reproduced true to type insuccessive generations of asexual propagation.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and represent thecharacteristics of the new Cornus cultivar ‘SUMMER GOLD’. These traitsin combination distinguish ‘SUMMER GOLD’ from all other varieties ofCornus known to the inventor. ‘SUMMER GOLD’ has not been tested underall possible conditions and phenotypic differences may be observed withvariations in environmental, climatic and cultural conditions, withouthowever any change in genotype.

-   -   1. The leaves of ‘SUMMER GOLD’ are mid green with a prominent        gold margin.    -   2. The gold margin of the foliage of ‘SUMMER GOLD’ is        approximately 15 mm in width at the widest extremes of a fully        expanded leaf.    -   3. ‘SUMMER GOLD’ maintains its golden variegation through the        summer    -   4. After one year's growth from initial grafting, ‘SUMMER GOLD’        is 1.0 meter-1.3 meters in height.    -   5. A three year old plant of ‘SUMMER GOLD’ is 2.2 meters-2.5        meters in height.    -   6. ‘SUMMER GOLD’ is hardy to USDA Zone 4.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying color drawings illustrate the overall appearance of thenew Cornus variety ‘SUMMER GOLD’ showing colors as true as it isreasonably possible to obtain in colored reproductions of this type. Thespecimen used in the drawings is a 2 year old tree which has been grownout of doors in Molalla, Oreg. Colors in the drawings may differ fromthe color values cited in the detailed botanical description, whichaccurately describe the actual colors of the new variety ‘SUMMER GOLD’.

The drawing labeled FIG. 1 shows a two year old plant of ‘SUMMER GOLD’growing in a 1 gallon container in Molalla, Oreg.

The drawing labeled FIG. 2 illustrates the inflorescence and theconspicuous white bracts of ‘SUMMER GOLD’. The bracts in this drawingare almost mature having changed from pale green to pure white exceptfor their tips. In addition, two of the depicted bracts exhibit tinypink spots or circular lesions which would be absent from a totallyunblemished inflorescence.

All drawings were made using conventional techniques and although colorsmay appear different from actual colors due to light reflectance theyare as accurate as possible by conventional photography.

DETAILED BOTANICAL DESCRIPTION OF THE PLANT

The following is a detailed description of the new cultivar ‘SUMMERGOLD’. Data was collected from a 5 year old plant grown in out of doorsin Molalla, Oreg. The color determinations are in accordance with the5th edition (2007) of The Royal Horticultural Society Colour Chart ofThe Royal Horticultural Society, London, England, except where generalcolor terms of ordinary dictionary significance are used. No chemicalswere used to treat the plants.

-   Botanical classification: Cornus.-   Species: Kousa.-   Common name: Kousa dogwood.-   Commercial classification: Deciduous flowering tree.-   Use: Landscape plant.-   Parentage: Cornus kousa (species, unpatented).-   Plant description:    -   -   Plant habit.—Upright.        -   Plant dimensions (1 year).—1 m-1.3 m in height and 60 cm in            width.        -   Plant dimensions (3 years).—2.2 m-2.5 m in height and 1 m in            width.        -   Plant hardiness.—USDA Zone 4-9.        -   Type.—Deciduous flowering tree.        -   Propagation.—Grafting, budding, or with semi-hardwood            cuttings.        -   Growth rate.—Vigorous, faster than other cultivars in the            species.        -   Cultural requirements.—Moist soil with good drainage.        -   Diseases and pests.—None known to the inventor.-   Branching habit: Ascending.-   Angle of emergence: 45 degrees away from the vertical.-   Stem:    -   -   Color.—199A.        -   Diameter of trunk at 10 cm height.—9 cm.        -   Surface.—Pubescent.        -   Lenticels.—Sparse, approximately 1 mm-3 mm apart.        -   Lenticel size on 2 year old branch.—0.5 mm in length by 0.25            mm in width.        -   Lenticel color.—155A.-   Foliage:    -   -   Arrangement.—Opposite.        -   Leaves.—Division: Simple. Shape: Ovate to elliptic.            Dimensions: 40 mm to 90 mm in length and 15 mm to 43 mm in            width. Tip: Acuminate. Base: Acute. Venation pattern:            Pinnate. Vein color (adaxial surface): Main vein 154D;            lateral veins evident only as depressions in the surface,            color as adjacent lamina. Vein color (abaxial surface): Main            vein 154D; lateral veins evident only as slight ridges in            the surface, color as adjacent lamina. Margin: Undulate.            Surface (both surfaces): Slightly rough due to the presence            of many fine whitish hairs. Leaf color: Ordinarily as            described below except lower leaves may exhibit bronzing or            reddening which inventor attributes to exposure to cold            temperatures. Where present, tips and tip margins of lower            leaves exhibit color ranging between 28A to 34A. Immature            leaf color (adaxial): Color as leaf emerges: 151A. Color            (marginal variegation): 4B when first expanded, becoming            darker 12C after one month. Color (leaf center): 145A when            first expanded, becoming darker 43C after one month.            Immature leaf color (abaxial): Color as leaf emerges: 151A.            Marginal variegation: 3D.-   Leaf center: 138A and 138B.    -   -   Mature leaf color (adaxial).—Outer margin: 10A. Leaf center:            146B and 35A.        -   Mature leaf color (abaxial).—Outer margin: 10C. Leaf center:            148C and 35B.        -   Leaf attachment.—Petiolate.        -   Petiole dimensions.—3 mm in length and 1.5 mm in diameter.        -   Petiole surface.—Rough.        -   Petiole color.—138B.-   Inflorescence:    -   -   Form.—Capitate simple cyme. Flowers single, arranged in            hemispheric cluster which is subtended by large showy floral            bracts.        -   Time and duration of flowering.—Flowers and bracts develop            simultaneously during late May. Bracts persist after            anthesis for up to 1 month.        -   Flowers.—Quantity of flowers per inflorescence: 30-35.            Dimensions: 4 mm-5 mm in height and width. Calyx: 4-lobed.            Petals, 4, separate, 3 mm in length and width, opening pale            green becoming creamy-white with 4 separate petals, oblong            with rounded apex.        -   Floral bracts.—Fused or unfused: Unfused. Shape: Elliptic to            broadly elliptic. Number: 4. Color (both surfaces):            Initially pale yellow-green 145C becoming white NN155D from            the base and eventually throughout. Surface texture (both):            Glabrous. Dimensions: Each bract: 55 mm in length and 22 mm            in width. All bracts together (widest point): 10 cm across.            Peduncle: 6 cm to 9 cm in length.        -   Reproductive organs.—Stamens: 4, alternate with petals, 1 mm            in length, 0.5 mm in diameter. Stamen color: N144B. Anther            dimensions: Approximately 1 mm in length and 0.5 mm in            width. Anther color: 153C. Pistil: 1, exserted. Style            terete, 5 mm in length, 1 mm in diameter, light green in            color. Capitate stigma, 1.0-1.5 mm in height and diameter,            light brown in color. Fruit: Develops in late August, ripens            in late September or October. Sparse, readily eaten by birds            and squirrels. Initially held upright on short peduncles            which lengthen with the season. Ripe fruit pendulous on            peduncles approximately 5 cm in length. Fruit texture and            surface: Fleshy drupe with rough surface. Fruit dimensions:            2.5-3.0 mm in diameter. Fruit color: Initially pink,            becoming bright raspberry red when ripe. Ovary inferior            Seeds, 0-2, irregular shape, mostly ovate 4-5 mm in width,            6-7 mm in length, hard, gray to light tan in color.

1. A new and distinct cultivar of Cornus plant named ‘SUMMER GOLD’ asdescribed and illustrated herein.